Quantic Croven has been an approved supplier of Qualified Parts List (QPL) crystals for more than fifty years. Qualified to MIL-PRF-3098 standards, we maintain an extensive array of approvals for crystals from 2.4 to 125 MHz. Our crystals are ideally suited for military, avionics, and space applications where reliability is paramount. Crystals ordered and marked in accordance with MIL-PRF-3098 have been fully qualified through Group B testing and are supplied with 100% screening and Group A inspection per the below table.
* Two sample units only for external dimensions. ** Applicable to overtone units and, when specified, fundamental units.
Group B Inspection – Product B Level Crystals
Inspection
Subgroup
Requirement Paragraph
Method Paragraph
Solderability
I*
3.7
4.10.3
Resistance to solvents (4 sample units)
I*
3.8
4.10.4
Shock (specified pulse)
I*
3.17
4.10.13
Vibration
I*
3.19.1
4.10.14.1
Thermal shock
I*
3.23
4.10.19.1
Seal
I*
3.24
4.10.26
Salt atmosphere (corrosion)
I*
3.27
4.10.21
Moisture resistance
I*
3.28
4.10.22
Terminal strength**
I*
3.30
4.10.23
Visual and mechanical examination (internal) **
I*
3.5, 3.6, 3.35
4.10.2.2
Bond strength (when specified) **
I*
3.31
4.10.24
Insulation resistance
II***
3.14
4.10.10
Aging
II***
3.29
4.10.27.1
* Testing period of 12 months (see 4.9.2). Tests eligible for reduced reporting frequency after 3 consecutive periods (see 4.7.5). ** Only two units are required. These two sample units shall be subjected to terminal strength, visual and mechanical (internal), and bond strength (when specified see 3.1). *** Testing period of 6 months (see 4.9.2) Tests eligible for reduced reporting frequency after 6 consecutive periods (see 4.7.5).